Esters of aminohalopyridyloxy acids

ABSTRACT

Compounds corresponding to the formula   WHEREIN X represents chloro, bromo, or fluoro; R represents alkyl of one to 12 carbon atoms or a radical having the formula (CH2)nOR3 wherein n represents an integer of from 2 to 4 and R3 represents lower alkyl of one to four carbon atoms or phenyl; M represents hydrogen or methyl; R1 represents hydrogen, loweralkyl of one to four carbon atoms, amino or loweralkylamino of one to four carbon atoms; and R2 represents hydrogen, X, loweralkyl, amino or loweralkylamino, with the proviso that one of R1 or R2 is always amino or loweralkylamino and the other of R1 and R2 is always other than amino or loweralkylamino are prepared. These compounds are useful as herbicides and as active agents in compositions used as herbicides.

United States Patent 1 McKendry Aug. 28, 1973 ESTERS OFAMINOHALOPYRIDYLOXY 221 Filed: July 26, 1971 21] Appl. No.: 166,308

[52] US. Cl. 260/295 R, 71/94 [51] Int. Cl. C07d 31/36 [58] Field ofSearch 260/295 R; 71/94 lirimary Examiner-Alan L. Rotman Attorney-S.Preston Jones, C. Kenneth Bjork et al.

[5 7] ABSTRACT Compounds corresponding to the formula wherein Xrepresents chloro, bromo, or fluoro; R represents alkyl of one to 12carbon atoms or a radical having the formula (CH,),,OR wherein nrepresents an integer of from 2 to 4 and R represents lower alkyl of oneto four carbon atoms or phenyl; M represents hydrogen or methyl; Rrepresents hydrogen, loweralkyl of one to four carbon atoms, amino orloweralkylamino of one to four carbon atoms; and R represents hydrogen,X, loweralkyl, amino or loweralkylamino, with the proviso that one of Ror R is always amino or loweralkylamino and the other of R and R isalways other than amino or loweralkylamino are prepared. These compoundsare useful as herbicides and as active agents in compositions used asherbicides.

6 Claims, No Drawings ESTERS OF AMINOIIALOPYRIDYLOXY ACIDS SUMMARY OFTHE INVENTION The present invention is directed to novel compoundscorresponding to the formula I O R -OCHCOOR In this and succeedingformulae, wherein X represents chloro, bromo, or fluoro; R representsalkyl of one to 12 carbon atoms or a radical having the formula(CH,),,OR wherein n represents an integer of from 2 to 4 and Rrepresents loweralkyl of one to four carbon atoms or phenyl; Mrepresents hydrogen or methyl; R represents hydrogen, loweralkyl of oneto four carbon atoms, amino or loweralkylamino of one to four carbonatoms; and R represents hydrogen, X, loweralkyl, amino orloweralkylamino, with the proviso that one of R or R is always amino orloweralkylamino and the other of R and R is always other than amino orloweralkylamino.

In the present specification and claims the term loweralkyl is employedto designate a straight, branched or cyclic alkyl radical containingfrom one to four carbon atoms. H

In the present specification and claims the term loweralkylamino asemployed designates either straight, branched chain or cyclic monoordialkylamino radicals wherein each alkyl group contains from one to fourcarbon atoms.

The present invention also is understood to encompass compounds whereinall the X substituents are the same as well as those wherein differenthalogens are present in the same compound.

For ease in understanding, it is to be understood that the term aminowhen used generically encompass compounds containing either an amino(-Nl-I,) radical or a loweralkylamino radical.

The present invention is also directed to plant husbandry and theraising of crops and is concerned with an agronomical practice andcomposition for improving the emergence, seed germination, seedlinggrowth and harvest of crop plants. This invention also relates toherbicidal compositions and to methods of inhibiting or controllingundesirable plant growth therewith in the presence of important economiccrops.

The active compounds of the present invention are crystalline solids oroils which are moderately soluble in common organic solvents.

The substituted aminohalopyridines of the present invention are preparedby the reduction of an aminohalopyridinol corresponding to the formulawherein R and R, are as hereinbefore defined, with a halo substitutedloweralkyl ester of acetic acid or propionic acid corresponding to theformula X-(EHCOOR wherein M, R and X are as hereinbefore defined.

The reaction is initiated by contacting the reactants together in thepresence of a retraction medium or solvent such as, for example,acetonitrile, dimethylformamide, p-dioxane, or dimethylsulfoxide and abase such as, for example, silver carbonate, potassium carbonate, sodiumcarbonate or metallic sodium. The reaction is carried out at atemperature in the range of from about 25 to about 150C., preferably attemperatures above 65C. The reaction consumes the reactants instoichiometric proportions, i.e., one equivalent of the pyridinolreactant per equivalent of the half-ester reactant. However, due to thenature of the pyridyloxy ester formation, it is preferred that an excessof the halo-ester reactant be employed.

The base is employed in amounts ranging from about 1 to about 2equivalents of base per equivalent of aminohalopyridinol reactant. Thepreferred amount is about 1 equivalent of base per equivalent ofpyridinol reactant.

In carrying out the reaction, the reactants, reaction medium andcatalyst are heated to the reaction temperature and maintained at thistemperature and in a state of agitation for a period of time of fromabout 0.5 to about 30 hours, until the reaction is complete. Thereaction mixture is thereafter filtered with or without prior cooling.The solvent is thereafter removed by evaporation under reduced pressure.The produce is purified by recrystallization from a solvent such as, forexample, carbon tetrachloride, n-hexane, cyclohexane or a methanol-watermixture or by the use of combinations of these solvents and/or by thesequential use of one or more solvents.

DESCRIPTION OF SOME PREFERRED EMBODIMENTS The following examplesillustrate the present invention and the manner by which it can bepracticed but, as such, should not be construed as limitations upon theoverall scope of the same.

EXAMPLE I 4-Amino3,5-dichloro-2-(pyridyloxy)acetic acidzethyl ester Amixture comprising 17.91 grams (0.1 mole) of 4-amino-3,S-dichloro-Z-pyridinol, l2 milliliters (0.11 mole) of ethylbromoacetate, milliliters of acetonitrile and 27.5 grams (0.1 mole) ofsilver carbonate were heated at reflux for 5% hours. The hot solution26.40 percent, respectively, as compared with the theoretical contentsof 40.75, 3.77, l0.57 and 26.79 percent, respectively, calculated forthe above-named structure.

EXAMPLE ll 4-Amino-3 ,5 ,6-trichloro-2-( pyridyloxy )acetic :ethyl esteracid- A mixture comprising -43 grams (0.02 mole) of 4-amino3,5,6-trichloro-2-pyridinol, 2.6 grams (0.02 mole) of potassiumcarbonate, 40 milliliters of acetonitrile and 3.2 milliliters (0.028)mole of ethyl bromoacetate were heated under reflux for 2% hours. Themixture was cooled and filtered. The solvent was thereafter removed byevaporation under reduced pressure. The4-amino-3,5,6-trichloro-2-(pyridyloxy )acetic acid- :ethyl ester productwas recovered in a yield of 3.85 grams (90.5 percent of theoretical) andmelting at 96-97C. The product was found by elemental analysis to havecarbon, hydrogen, nitrogen and chlorine contents of 36.4, 3.2, 9.4 and34.8 percent, respectively, as compared with the theoretical contents of38.1, 3.0, 9.4 and 35.5 percent, respectively, calculated for theabove-named structure.

The following compounds of the present invention are prepared inaccordance with the methods hereinbefore set forth.

4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid: methyl ester having amelting point of l l9-l2lC.;

4-Am'ino-3,5,6-trichloro-2-(pyridyloxy)acetic acid: 2-butoxy ethyl esterhaving a molecular weight of 37 l'.5 l;

4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid: butyl ester having amelting point of l31l33C.;

2- [4-Amino-3,5-dichloro-2-(pyridyloxy lpropionic acidzmethyl esterhaving a molecular weight of 265.01;

6-Amino-3,5-dichloro-4methyl-2-(pyridyloxy)- acetic acidzmethyl esterhaving a molecular weight of 265.01;

2-[6-Methylamino-3,5-dichloro-4butyl-2-(pyridyloxy) ]propionicacid:butyl ester having a molecular weight of 374.90;

2-[6-Dibutylamino-3,4,5-trichloro-2-(pyridyloxy)]propionic acidzethylester having a molecular weight of 425.55;

4 4-Methylamino-3,S-dibromo-Z-(pyridyloxy )acetic acidz4-methoxy butylester having a molecular weight 2-[6-Methylamino-3,5-difluoro-4-methyl-2-(pyridyloxy)]propionicacidz3-butoxy propyl ester having a molecular weight of 360.17;

2-[4-Amino-3,5-dichloro-2-(pyridyloxy)]propionic acidzethyl ester havinga melting point of 78-83C.;

2-[4-Amino-3,5,6-trichloro-2-(pyridyloxy)lpropionic acidzethyl esterhaving a molecular weight of 3 l- 3.48;

4-[Amino-3,5,6-trichloro'2-(pyridyloxy)lacetic acid zphenoxy methylhaving a molecular weight of 377.52;

2-{ 6-A mino-3,5-dichloro-4-methyl-2-( pyridyloxy) propionicacidzcyclopropyl ester having a molecular weight of 304.04;

2-[fi-Cyclopropylamino-3,5-difluoro-4-butyL2- (pyridyloxy)}propionicacid1cyclobutyl ester having a molecular weight of 327.16; and

2-[6-lsopropylamino-3,5-dichloro-4-propyl-2- (pyridyloxy)]propionicacidzisopropyl ester having a molecular weight of 377.09.

In accordance with the present invention, it has been discovered thatthe substituted aminohalopyridyloxy esters of the present invention areuseful as herbicides. In accordance with this invention, a method forcontrolling or inhibiting the growth of undesirable plant species isprovided which comprises applying to plants, plant parts or theirhabitat, an eflective or growth inhibiting amount of at least one of thesubstituted aminohalopyridyloxy esters as set forth hereinabove.

An outstanding feature of the present invention is the ability of theester compounds to control, either by post-emergent or pre-emergentapplication, the growth of small seeded grasses and broadleaf plants,such as, for example, barnyard grass, crabgrass, yellow foxtail, Johnsongrass, wild oats, bindweed, pigweed, ragweed and wild mustard. Thisability is of utmost importance since the compounds are not usuallyharmful to economical, large seeded crop plants, such as, for example,corn, rice, soybeans or wheat. This feature allows for selective controlof the undesirable small seeded plants in the presence of the economicallarge seeded crop plants.

The application of the compounds of the present invention to plants andplant parts and their habitats, gives rise to varying degrees ofresponse to the compounds depending upon the nature of the plant orseed, the stage of growth or maturity of the plant, the specificcompound employed, and the dosage at which plant or plant part orhabitat exposure to the compound is carried out, as well asenvironmental conditions. When large dosages of many of the compoundsare applied to the foliage of undesirable plants, a substantiallycomplete kill is obtained. Soil or foliar applications of more dilutedosages of many of the compounds suppress the growth of the gerrninantseeds and seedlings of many undesirable grasses while having little orno effect upon the seeds, emerging seedlings or established plants ofmany desirable crop plants. Thus, many of the ester compounds can beemployed for the selective control of emerging seedlings of undesirableweeds in plantings or stands of desirable crop plants.

The minimum amount of active compound applied should be that which iseffective in controlling and/or killing undesirable plant growth.Ordinarily, for preemergent control, good results are obtained when from0.01 to 50 pounds or more of at least one of the activeaminohalopyridyloxy ester compounds are applied per acre. in foilagetreatments, good results are obtained when from 0.1 to 200 pounds ofactive compound per acre are employed. In selective applications tofoliage for the control of many undesirable weeds in the presence ofdesired crop plants, a uniform dosage of from about 1.0 to 75 pounds ofof active compound can be employed. In all selective applications, theexact dosage to be employed is dependent upon the resistance of the cropplant or their seeds to the ester compounds.

The present invention can be carried out by directly employing the estercompounds singly or in combination with each other. However, the presentinvention also embraces the employment of liquid, granular, encapsulatedor dust compositions containing at least one of said compounds. In suchusage, the compound or compounds can be modified with one or more of aplurality of chemically inert additarnents or pesticidal materialsincluding solvents or other liquid carriers, surface active dispersingagents or coarsely or finely divided inert solids. The augmentedcompositions are also adapted to be employed as concentrates andsubsequently diluted with additional inert carrier, to produce othercompositions in the form of dusts, sprays, granules, washes or drenches.ln compositions where the additament is a coarsely or finely dividedsolid, a surface active agent or the combination of a surface activeagent and a liquid additament, the added material cooperates with theactive component so as to facilitate the invention. Whether thecomposition is employed in liquid form, as a wettable powder, or as agranular or encapsulated material, the active compound will normally bepresent in an amount of from about 5 to about 95 percent by weight ofthe total composition.

In the preparation of dust compositions, the toxicant products can becompounded with any of the finely divided solids, such as, for example,pyrophyllite, talc, chalk, gypsum, fuller's earth, bentonite,attapulgite, and the like. In such operations, the finely dividedcarrier is ground or mixed with the toxicant or wet with a solution ofthe toxicant in a volatile organic solvent. Also, such dust compositionswhen employed as com centrates can be dispersed in water, with orwithout the aid of dispersing agents to form spray mixtures.

Granular formulations are usually prepared by impregnating a solution ofthe toxicant in a volatile organic solvent onto a bed of coarselydivided clays, such as, for example, attapulgite, bentonite, diatomite,or the like.

Similarly, the toxicant products can be compounded with a suitablewater-immiscible organic liquid and a surface active dispersing agent toproduce an emulsifiable concentrate which can be further diluted withwater and oil to form spray mixtures in the form of oilin-wateremulsions. In such compositions, the carrier comprises an aqueousemulsion, i.e., a mixture of water-immiscible solvent, emulsifying agentand water. Preferred dispersing agents which can be employed in thesecompositions, are oil-soluble materials including non-ionic emulsifierssuch as, for example, the condensation products of alkylene oxides withthe inorganic acids, polyoxyethylene derivatives or sorbitan esters,complex ether alcohols and the like. Also, oil-soluble ionic emulsifyingagents such as mahogany soaps can be used. Suitable organic liquidswhich can be employed in the composition include, for example, petroleumoils and distillates, toluene, liquid halohydrocarbons and syntheticorganic oils. The surface-active dispersing agents are usually employedin liquid compositions and in the amount of from 0.1 to 20 percent byweight of the combined weight of the dispersing agent and activecompound.

In addition, other liquid compositions containing the desired amount ofeffective agent can be prepared by dissolving the toxicant in an organicliquid such as, for example, acetone, methylene chloride, chlorobenzeneand petroleum distillates. The preferred organic solvent carriers arethose which are adapted to accomplish the penetration and impregnationof the environment and particularly soil with the toxicant compounds andare of such volatility as to leave little permanent residue thereon.Particularly desirable carriers are the petroleum distillates boilingalmost entirely under 400F. at atmospheric pressure and having a flashpoint above F. The proportion of the compounds of this inventionemployed in a suitable solvent may vary from about 2 to about 50 percentor higher.

In further embodiments, the compounds as employed in accordance with thepresent invention, or compositions containing the same, can beadvantageously employed in the present invention in combination with oneor more pesticidal or preservative compounds. In such embodiments, thepesticidal or preservative compound is employed either as a supplementaltoxicant or as an additament. Representative operable pesticidal orpreservative compounds include substituted phenols, cresols, substitutedcresols and their metal salts, bisphenols and thiobisphenols;halogenated calicylanilides, organo-sulfur compounds, carbamatecompounds, quaternary ammonium compounds, organometallic compounds,inorganic salts and miscellaneous other compounds, such as phenol,cresol, trichlorophenols, tetrachlorophenols, pentrachlorophenol, pchloro-m-cresol, sodium pentachlorophenol and other sodium, potassium,etc. salts of the phenols, substituted phenols, cresols and substitutedcresols, diand tribrominated salicylanilides,2,2'-methylenebis(3,4,6-trichlorophenol),2,2'-thiobis(4,6-dichlorophenoxide), halogenated trifluoromethylsalicylanilide, disodium ethylenebisthiocarbamate, sodiumN-methyldithiocarbamate, zinc dimethyldithiocarbamate,Z-mercaptobenzothiazole, 3 ,S-dimethyltetrahydro-l ,3 ,5-2H-thioadiazine-Z-thione, 2,3 -dinitro-l ,4-dithiaanathraquinone,dodecyl pyridinium chloride, alkyl dimethyl benzyl ammonium chloride,dialkyl dimethylammonium chloride, bis-tributyltin oxide,bistripropyltin oxide, copper pentachlorophenate, copper8-hydroxyquinolate, sodium borate, 9-undecylenic acid,l0,l0'-oxybisphenoxarsine, l-(3-chloroallyl)-3,5,7-triaza-l-azonia-adarnantane chloride, l,4- bromobisacetobutene andsubstituted phosphorothioates (soil applied insecticides).

In application to an area to be treated, the compounds of this inventionmay be applied by spraying or by the use of mechanical spreaders inaccordance with conventional practice. With respect to application,however, it will be noted that, depending upon the particularcircumstances encountered, one method of application may be preferableover others. Thus, for example, for preferred pre-emergence applicationit has been found very satisfactory to apply the active compound in aliquid spray or on granules and incorporate it into the soil.

in a further method, the distribution can be accomplished by introducinga toxicant or toxicants into the 82-[4-Amino-3,S-dichloro-Z-(pyridyloxy)]propionic acid:methyl ester;

4-Amino-o-3,5-dichloro-2-(pyridyloxy)acetic ethyl ester;

acid:

water employed to irrigate the soil. In this method, the 54-Amin0-3,5,6-trichloro-2-( pyridyloxy)acetic acidamount of water can bevaried in accordance with the :ethyl ester;2-[4-Methylamino-3,5-dichloro-4-butyl-2- moisture equivalent or fieldcapacity of the soil in order (pyri yl-oxy)]propionic acid:butyl ester;to obtain the desired depth of distribution of the toxi-4-Amin0-3,S-dichloro-Z-(pytidyloxy )acetic acidzbucant. tyl ester;

The following embodiments are illustrative of the4-Amino-3,5,6-trichloro-2-(pyridyloxy)acetic present methods.acid:2-butoxy ethyl ester;

2-[6-Amino-3,5-dichloro-4methyl-2-(pyridyloxy)]- EXAMPLE aceticacid:methyl ester; Forty-five parts by weight of 2-[4-dibutylamino-2-[6-Dibutylarnino-3,4,5-trichl0ro-2-(pyridyloxy)]- 3,4,5-trichloro-2pyridyloxy)]propionic acidzether l5 propionic acid:ethyl ester; ester ismixed and ground with 5 parts by weight of Tri-4-Methylamino-3,S-dibromo-Z-(pyridyloxy )acetic ton X-l 55 surfactant(an alkylated aryl polyether alcoacidz4-methoxy butyl ester; hol) toprepare a water-dispersible concentrate compo-2-[6-Methylamino-3,5-difluoro-4methyl-2- sition containing 90 percent byweight of the ester com- (pyridyl0xy)]propionic acidz3-butoxy propylester; poumi 4-Amino-3,5-dichloro-2-(pyridyloxy)propionic acid- In afurther operation, parts by weight of 6-aminoyl ester; and3,5-dichloro-2-(pyridyloxy)acetic acid:methyl ester, 10 p py -p py partsby weight of Triton X-155surfactant and 65 parts (py y ynp p W PYesterby weight of xylene are mixed together to prepare an 25 of thesecoflcemmte compositifms are emulsifiable concentrate compositioncontaining 25 Persed Separate P of Wale! to Provlde aqueous percent byweight f said ester compoun compositions, each containing 0.44 pound ofone of the A mixture of 10 parts by weight of 2-[6-isopropylmp f P l ofultimate qf 3,5 dich]0m 4 pmpy| 2 (pyridy1oxy)lpmpionic acid mixture.The diluted compositions have very desirable :isopropyl ester, 10 partsby weight of 2-[4- 3O 'i f and f l g Propemes and are adaptedmethylamino 35 dichl0m 4 buty1 2 (pyridyloxynprm distribute growthinhibiting amounts of the ester compionic acidzbutyl ester, 0.1 part ofNacconol NR deterpound on plant parts' gent (alkyl sulfonate), 0.1 partof Daxad No. 27 (a po- EXAMPLE v lymerized sodium salt of benzoid alkylsulfonic acids) and 200 parts of water are ball-milled together to pre-3 5 Representauve products of the Present mention pare a waterdispersible liquid concentrate composition were evaluate? for thepost'emergem of barn containing 20 parts by weight of the mixed pyridineyard grass, wild mustard, crabgrass, pigweed, yellow compounds Theconcemtate compositions thus foxtall and blndweed. In these evaluat ons,plots of the pared can be dispersed in water to prepare aqueous boveplant specles growth to a height about 4 compositions which have verydesirable wetting and 40 mche? used Aqueous .Spray each penetratingproperties and are adapted to distribute grconwnmg 4000 g a gwenammqhalopyndymxy owth inhibiting amounts of the pyridine compound one.ster compound pelhmflhon parts of .ulumate composl plant parts tion,were prepared in accordance with the procedures EXAMPLE W of Example IV,and each separate composition was applied to a separate plot. Theapplication was made to In spearate operations, aqueous compositionsconthe point of run-off and was carried out with conventainingaminohalopyridyloxy ester compounds are pretional spraying equipment.Other plots were sprayed pared as follows: with similar compositionscontaining no toxicant to Four parts by weight of one of the estercompounds, serve as controls. Thereafter, the plots were maintained 0.08part of sorbitan trioleate (Span 85), and 0.02 part under conditionsconductive for plant growth. Two of a sorbitan monoleat'epolyoxyethylene derivative weeks after treatment, the plots wereexamined for (Tween are dispersed in 40 milliliters of acetone to plantgrowth and evaluated. The results of the examinaproduce a concentratecomposition in-the form of a wation of the treated plots were set forthin the following ter-soluble liquid containing one of the estercomtable.

Compound employed Percent kill and control of Wild Crab- Pig- BarnyardYellow Bind- 4-umino-3,5-dichloro-2-( pyridyloxy) acetic acid:ethy1ester.-- 4-amino-3,5,6-trlchloro-2-(pyridyloxy) acetic acldzethyl ester.4-amlno-3.5-dicliloro-2-gpyridyloxy) acetic acldzbutyl ester4-nmino3,5-dlehloro-iZ-(pyrldyloxy) acetic acidzmethyl esterZ-H-aml$,5-dlchl0ro-2-(pyridyloxy)]-propionic aridtethyl ester Controlpounds as the sole active agent. The conpounds em- 65 ployed in theseprocedures include the following:

4-Amino-3,S-dichloro-Z-(pyridyloxy)acetic methyl ester;

acid:

Aqueous compositions of various ester compounds prepared in accordancewith Example IV were employed for pre-emergent applications on plotsimmediately after they were seeded with crabgrass, wild oats, barnyardgrass, wild mustard, pigweed, yellow foxtail and bindweed. Other plotssimilarly seeded with the ing the same plant species were treated withcompositions containing no toxicant, to serve as controls. Thereafter,the plots were held for a period of two weeks under conditionsconductive for good plant above plant species were treated with likecompositions growth A the d f hi i d h plots were examcontaining notoxicant to serve as control plots. The i d t d t ine th degree of killand control of the treating applications were carried out by drenchingthe l m I th control plots, all of the plants were growsoil with theaqueous compositions to obtain a treating i idl d no kill or t l f any fth plants rate of 20 Pounds P acre' Thereafter, the Plots were 10 couldbe found. In the ester treated plot, there was submaintained underconditions conductive for good plant i ll complete kill d Control of iloats, Joh growth. Two weeks after treatment, the plots were exon grass,wild mustard, pigweed, bindweed, barnyard amined to determine thepercent plant growth and grass and yellow foxtail and no injury could befound evaluated. The results of the examinations are set forth to thesoybean plants which were thriving and growing in the following table.profusely.

TABLE B Compound employed Percent kill and control of4-amino-3,5-diehloro-2-(pyridyloxy)acetic acidznthyl nsterMimino-3,5,6-trichloro-2(pyridyloxy)acetic acidzothyl ester.d-arnii1o3,5-dieliloro-2-(Dyridyloxyhwotic acidzhutyl ester.4-umi1\o-3,5-di(:hloro'2-(pyridyloxy)acetic aeidnnethyl ester.

2-[4-umino3,5-dichloro-2-( pyrldylox y)]-propionic acid ethyl ester.

Control EXAMPLE VII 2-[4-Amino-3,5-dichloro-2-(pyridyloxy)]propionicacidzethyl ester was employed for the selective control of emergingseedlings of the weed plants, barnyard grass, yellow foxtail, Johnsongrass, pigweed, ragweed and wild mustard in plots seeded with theabove-named plant species and the crop plant wheat. The plots weretreated with aqueous compositions prepared as set forth in Example IVcontaining the above-named compound as the sole toxicant therein. Otherplots similarly seeded with the above-named plant species were treatedwith aqueous compositions containing no toxicant to serve as controlplots. The treating applications were carried out by drenching the soilwith the aqueous compositions to obtain a treating rate of 1 pound peracre. Thereafter, the plots were maintained under conditions conductiveto good plant growth. Examination of the plots two weeks after treatmentshowed substantially complete kill and control of all of the weed plantspecies and profuse growth of wheat. In the control plots, no kill orcontrol of any of the plant species could be ascertained.

EXAMPLE VIII 4-Amino-3,S-dichloro-2-(pyridyloxy)acetic acid: butyl esterwas evaluated for the selective postemergent control of wild oats,Johnson grass, wild mustard, pigweed, bindweed, barnyard grass andyellow foxtail in plots containing these plant species and soybeanplants. In this evaluation, the plants were of a height of about 4inches. An aqueous spray composition containing 4,000 parts of thecompound per million parts of ultimate composition and prepared inaccordance with the procedures of Example IV, was applied to a plotcontaining the above plant species. The application was made to thepoint of run-off employing conventional spraying equipment. Other plotscontain- PREPARATION OF STARTING MATERIALS The 4- and 6-amino-(diortri-)halo-2-pyn'dinols employed as starting materials can be prepared byreacting an appropriate 4- or 6- amino-trior tetrahalopyridine,containing a halogen atom in the 2-position with an aqueous solution ofan alkali metal hydroxide at a temperature of from about l20to about200C.

What is claimed is:

1. A compound corresponding to the formula X-QX 11 --OCIICOOR wherein Xrepresents chloro, bromo, or fluoro; R represents alkyl of one to 12carbon atoms or a radical having the formula (CH ),,OR wherein nrepresents an integer of from 2 to 4 and R represents lower alkyl of oneto four carbon atoms or phenyl; M represents hydrogen or methyl; Rrepresents hydrogen, loweralkyl of one to four carbon atoms, amino orloweralkylamino of one to four carbon atoms; and R represents hydrogen,X, loweralkyl, amino or loweralkylamino, with the proviso that one of Ror R is always amino or loweralkylamino and the other of R and R isalways other than amino or lowerallcylamino.

2. The compound of claim 1 which is 4-Amino-3,5-dichloro-Z-(pyridyloxy)acetic acid:methyl ester.

3. The compound of claim 1 which is 4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid:ethyl ester.

4. The compound of claim 1 which is 4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid:butyl ester.

5. The compound of claim I which is 2-[4-Amino-3,5-dichloro-2-(pyridyloxy)lpropionic acid:ethyl ester.

6. The compound of claim 1 which is 4-Amino-3,5,6-trichloro-2-(pyridyloxy)acetic acidrethyl ester.

PO-105O UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3 L755 3 9 I Dated Auust 28, 1973 Inventofls) Lennon M. McKendrv It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column-l, line 58, delete substitute reaction- "reduction" and Column 2,line 20, delete "half-ester" and substitute halo-ester-- line ll, delete"retraction" and substitute -reactionv line 37, delete "produce" andsubstitute product Column 3, line 32, insert before 3,5,6.

line 60, insert before methyl line 65, delete "374.90" and substituteColumn 6, line 51, delete "anathraquinone" and substitute anthraquinone.

Column 8, line 3, delete "0- line 12, insert after the 4 line 50, delete"conductive" and substitute conducive.

Column 9, line 10, delete "conductive" and substitute conducive. I

line 44, delete "conductive" and substitute conducive.

UNITED STATES PATENT OFFICE Page 2 CERTIFICATE OF CORRECTION Patent NDated August 28,

Inventor(s) Lennon M. McKendry It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 10, line L delete "conductive" and substitute conducive Signedand sealed this 25th day of June 197R.

EDWARD M.FLETCHER,JR.

Commissioner of Patents Attesting Officer ORM po'wso uscoMM-oc some-peeQ U.S. GOVERNMENT PRINTING OFFICE 2 9,9 0-356-335,

2. The compound of claim 1 which is4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid:methyl ester.
 3. Thecompound of claim 1 which is 4-Amino-3,5-dichloro-2-(pyridyloxy)aceticacid:ethyl ester.
 4. The compound of claim 1 which is4-Amino-3,5-dichloro-2-(pyridyloxy)acetic acid:butyl ester.
 5. Thecompound of claim 1 which is2-(4-Amino-3,5-dichloro-2-(pyridyloxy))propionic acid:ethyl ester. 6.The compound of claim 1 which is4-Amino-3,5,6-trichloro-2-(pyridyloxy)acetic acid:ethyl ester.